Comparison of adaptive and robust receivers for signal detection in ambient underwater noise

Three receivers are compared for the detection of a known signal in additive ambient underwater noise of seagoing merchant vessels. These receivers are: the matched filter, which is the classical linear receiver based on a Gaussian assumption; the correlation-limiter, which is the Neyman-Pearson minimax robust receiver when the noise uncertainty is modeled as a mixture process with a Gaussian nominal; and the Gaussian-Gaussian mixture likelihood ratio receiver. This last receiver is adaptive in the sense that it is based on a parametric model whose parameters are computed from the actual data. The principal results of this study are that, in terms of the receiving operating curves, the adaptive receiver performs better than the linear one which, in turn, performs slightly better than the robust correlator-limiter. This study illustrates, for one particular noise sample, the merit of the simple mixture model in adaptive processing for signal detection purposes